The present invention relates to a camera, more particularly to an automatic exposure camera which can automatically control a shutter time in accordance with an object.
In an aperture preferential type automatic exposure camera, a film sensitivity and an aperture information are previously set on the side of a camera and the thus set exposure is given to an automatic exposure circuit as a variable of the shutter time.
As a setting means of the film sensitivity (ASA) and the aperture value in such kind of automatic exposure cameras, there has been such construction shown in FIG. 1. That is, reference numeral 1 is a diaphragm ring rotatably supported on a camera lens housing, and this diaphragm ring 1 is provided with an ASA setting ring 2. On a plate surface of the ASA setting ring 2 are formed a number of through-holes 2a which successively vary an opening area, and on a plate surface of the diaphragm ring 1 corresponding to the through-hole 2a is formed an elongate hole 1a, and light from an object is transmitted to the side of a light receiving element 3 fixed through the through-hole 2a and the elongate hole 1a. Further, in this case, the diaphragm ring 1 and the ASA setting ring 2 are frictionally coupled or click-coupled, so that when the diaphragm ring 1 is rotated along a scale 4 marked on the lens housing, the ASA setting ring 2 is integrally rotated to press the diaphragm ring 1, and as a result, if the ASA setting ring 2 is rotated, it is rotated along an ASA scale 5 marked on the diaphragm ring 1 regardless of the diaphragm ring 1.
In the automatic exposure camera having such construction, the diaphragm ring 1 is firstly pressed, the ASA setting ring 2 is only rotated, and after setting the film sensitivity, the diaphragm ring 1 is set on a desired scale, thereby adjusting light from an object transmitted to the light receiving element 3 through the through-hole 2a and controlling the shutter time.
According to this construction, however, the diaphragm ring and the ASA setting ring are click-coupled or frictionally coupled, so that operation for setting the film sensitivity becomes troublesome and mechanically complicated. Further, the diaphragm ring and the ASA setting ring are independently and relatively rotated against the fixed light receiving element, so that a lengthwise size of the elongate hole on the diaphragm ring and a rotating angle of the ASA setting ring require the maximum rotating angle of the diaphragm ring+the maximum rotating angle of the ASA setting ring, and it is difficult to adjust both the rings when assembling.
The present invention also relates to a camera provided with an autostrobe for making flash photography possible.
Hitherto, this kind of cameras combined with an autostrobe requires the following various operations.
(1) The ASA sensitivity of a film should be set. PA1 (2) An iris on the side of a camera should be set to an F value matched with efficiency of the autostrobo. PA1 (3) An electric power source on the side of the strobo is set to ON.
Therefore, for flash photography with such a camera, it takes time and is troublesome, and if one of the above operations is ignored, precious photographs are spoiled.